Network Working Group Y. Lee
Internet Draft Huawei
Intended status: Standard R. Casellas
Expires: September 2011 CTTC
C. Margaria
NSN
O. G. de Dios
Telefonica
March 4, 2011
PCEP Extension for WSON Routing and Wavelength Assignment
draft-lee-pce-wson-rwa-ext-01.txt
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Abstract
This draft provides the Path Computation Element communication
Protocol (PCEP) extensions for the support of Routing and Wavelength
Assignment (RWA) in Wavelength Switched Optical Networks (WSON).
Lightpath provisioning in WSONs requires a routing and wavelength
assignment (RWA) process. From a path computation perspective,
wavelength assignment is the process of determining which wavelength
can be used on each hop of a path and forms an additional routing
constraint to optical light path computation.
Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 0.
Table of Contents
1. Introduction...................................................3
2. WSON PCE Architectures and Requirements........................6
2.1. Encoding of a new RWA path request........................7
2.1.1. Wavelength Range Constraint..........................9
2.1.2. Signal processing capability restrictions............9
2.1.2.1. MODULATION-FORMAT TLV..........................11
2.1.2.2. FEC TLV........................................11
2.1.3. New XRO sub-object: signal processing exclusion.....12
2.1.4. IRO sub-object: signal processing inclusion.........13
2.2. Encoding of a RWA Path Reply.............................13
2.3. Error Indicator..........................................14
2.4. NO-PATH Indicator........................................14
3. Manageability Considerations..................................15
3.1. Control of Function and Policy...........................15
3.2. Information and Data Models, e.g. MIB module.............15
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3.3. Liveness Detection and Monitoring........................16
3.4. Verifying Correct Operation..............................16
3.5. Requirements on Other Protocols and Functional Components16
3.6. Impact on Network Operation..............................16
4. Security Considerations.......................................16
5. IANA Considerations...........................................16
6. Acknowledgments...............................................17
7. References....................................................17
7.1. Normative References.....................................17
7.2. Informative References...................................17
8. Contributors..................................................19
Authors' Addresses...............................................19
Intellectual Property Statement..................................19
Disclaimer of Validity...........................................20
1. Introduction
[RFC4655] defines the PCE based Architecture and explains how a Path
Computation Element (PCE) may compute Label Switched Paths (LSP) in
Multiprotocol Label Switching Traffic Engineering (MPLS-TE) and
Generalized MPLS (GMPLS) networks at the request of Path Computation
Clients (PCCs). A PCC is shown to be any network component that
makes such a request and may be for instance an Optical Switching
Element within a Wavelength Division Multiplexing (WDM) network.
The PCE, itself, can be located anywhere within the network, and may
be within an optical switching element, a Network Management System
(NMS) or Operational Support System (OSS), or may be an independent
network server.
The PCE communications Protocol (PCEP) is the communication protocol
used between PCC and PCE, and may also be used between cooperating
PCEs. [RFC4657] sets out the common protocol requirements for PCEP.
Additional application-specific requirements for PCEP are deferred
to separate documents.
This document provides the PCEP extension for the support of Routing
and Wavelength Assignment (RWA) in Wavelength Switched Optical
Networks (WSON) based on the requirements specified in [PCE-RWA].
WSON refers to WDM based optical networks in which switching is
performed selectively based on the wavelength of an optical signal.
In this document, it is assumed that wavelength converters require
electrical signal regeneration. Consequently, WSONs can be
transparent (A transparent optical network is made up of optical
devices that can switch but not convert from one wavelength to
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another, all within the optical domain) or translucent (3R
regenerators are sparsely placed in the network).
A LSC Label Switched Path (LSP) may span one or several transparent
segments, which are delimited by 3R regenerators (typically with
electronic regenerator and wavelength conversion). Each transparent
segment or path in WSON is referred to as an optical path. An
optical path may span multiple fiber links and the path should be
assigned the same wavelength for each link. In such case, the
optical path is said to satisfy the wavelength-continuity
constraint. Figure 1 illustrates the relationship between a LSC LSP
and transparent segments (optical paths).
+---+ +-----+ +-----+ +-----+ +-----+
| |I1 | | | | | | I2| |
| |o------| |-------[(3R) ]------| |--------o| |
| | | | | | | | | |
+---+ +-----+ +-----+ +-----+ +-----+
[X LSC] [LSC LSC] [LSC LSC] [LSC X] SwCap
<-------> <-------> <-----> <------->
<-----------------------> <---------------------->
Transparent Segment Transparent Segment
<------------------------------------------------->
LSC LSP
Figure 1: Illustration of a LSC LSP and transparent segments
Note that two optical paths within a WSON LSP need not operate on
the same wavelength (due to the wavelength conversion capabilities).
Two optical paths that share a common fiber link cannot be assigned
the same wavelength. To do otherwise would result in both signals
interfering with each other. Note that advanced additional
multiplexing techniques such as polarization based multiplexing are
not addressed in this document since the physical layer aspects are
not currently standardized. Therefore, assigning the proper
wavelength on a lightpath is an essential requirement in the optical
path computation process.
When a switching node has the ability to perform wavelength
conversion, the wavelength-continuity constraint can be relaxed, and
a LSC Label Switched Path (LSP) may use different wavelengths on
different links along its route from origin to destination. It is,
however, to be noted that wavelength converters may be limited due
to their relatively high cost, while the number of WDM channels that
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can be supported in a fiber is also limited. As a WSON can be
composed of network nodes that cannot perform wavelength conversion,
nodes with limited wavelength conversion, and nodes with full
wavelength conversion abilities, wavelength assignment is an
additional routing constraint to be considered in all lightpath
computation.
[Ed note: in general, WSON LSC may not be the only switching layer
with switching constraints. From a GMPLS/PCEP perspective,
wavelength assignment corresponds to label allocation. This document
should align with GMPLS extensions for PCEP. Wavelength restrictions
and constraints should be formulated in terms of labels (i.e.
LABEL_SET, SUGGESTED_LABEL, UPSTREAM_LABEL, etc.)
[Ed Note] For example, within a translucent WSON, a LSC LSP may be
established between interfaces I1 and I2, spanning 2 transparent
segments (optical paths) where the wavelength continuity constraint
applies (i.e. the same unique wavelength MUST be assigned to the LSP
at each TE link of the segment). If the LSC LSP induced a Forwarding
Adjacency / TE link, the switching capabilities of the TE link would
be [X X] where X < LSC (PSC, TDM, ...).
In addition to those label switching constraints, each optical path
is constrained by the optical signal quality. The optical signal
quality depends first on the optical sender and receiver
capabilities. Second contributors to optical signal constraints are
the optical elements used on the path (optical fibers, amplifiers,
boosters, optical components). All those elements have an impact on
the optical signal quality that limits the ability of the optical
path to carry traffic. In order to improve the signal quality and
limit some optical effects several advanced modulation processing
are used. Those modulation properties contribute not only to optical
signal quality checks but also constrain the selection of sender and
receiver, as they should have matching signal processing
capabilities.
The optical modulation properties, also referred to as signal
compatibility, are already considered in signaling in [RWA-Encode]
and [WSON-OSPF].
This document includes signal compatibility constraint as part of
RWA path computation. That is, the signal processing capabilities
(e.g., modulation and FEC) must be compatible between the sender and
the receiver of the optical path across all optical elements.
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This document, however, does not address optical impairments as part
of RWA path computation. See [WSON-Imp] and [PSVP-Imp] for more
information on optical impairments and GMPLS.
.
Listed below are some relevant drafts addressed in the IETF CCAMP
WG.
. WSON RWA Framework:
o draft-ietf-ccamp-rwa-wson-framework
. Label switching constraints:
o draft-ietf-ccamp-general-constraint-encode
o draft-ietf-ccamp-rwa-wson-encode
o draft-ietf-ccamp-rwa-info
. Signal processing capabilities:
o draft-ietf-ccamp-rwa-wson-encode
o draft-ietf-ccamp-wson-signal-compatibility-ospf
o draft-ietf-ccamp-wson-signaling
. Optical Impairment:
o draft-ietf-ccamp-wson-impairments
o draft-agraz-ccamp-wson-impairment-rsvp
o draft-eb-ccamp-ospf-wson-impairments
The remainder of this document uses terminology from [RFC4655].
2. WSON PCE Architectures and Requirements
Figure 2 shows one typical PCE based implementation, which is
referred to as Combined Process (R&WA). With this architecture, the
two processes of routing and wavelength assignment are accessed via
a single PCE. This architecture is the base architecture from which
the requirements have been specified in [PCE-RWA] and the PCEP
extensions that are going to be specified in this document based on
this architecture.
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+----------------------------+
+-----+ | +-------+ +--+ |
| | | |Routing| |WA| |
| PCC |<----->| +-------+ +--+ |
| | | |
+-----+ | PCE |
+----------------------------+
Figure 2: Combined Process (R&WA) architecture
2.1. Encoding of a new RWA path request
The current RP object is used to indicate routing related
information in a new path request per [RFC5440]. Since a new RWA
path request involves both routing and wavelength assignment, the
wavelength assignment related information in the request SHOULD be
coupled in the path request.
[Ed note: align with [GMPLS-PCEP] in the sense that Wavelength
Assignment is a particular case of Label Allocation]
Label allocation can be performed by the PCE by different means:
a) By means of Explicit Label Control, in the sense that one (or
two) allocated labels MAY appear after an interface route
subobject.
b) By means of a Suggested Label (and, for bidirectional LSPs, an
Upstream Label) provided by the PCE
c) By means of a Label Set, containing one or more allocated Labels,
provided by the PCE.
Note that in the b) and c) cases, except when c) includes only one
Label, the label allocation can be considered an optimization or
suggestion, allowing to be completed with distributed label
allocation (performed during signaling).
Additionally, given a range of potential labels to allocate, the
request SHOULD convey the heuristic / mechanism to the allocation,
including vendor-specific approaches.
The format of a PCReq message after incorporating the WA object is
as follows:
<PCReq Message> ::= <Common Header>
[<svec-list>]
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<request-list>
Where:
<request-list>::=<request>[<request-list>]
<request>::= <RP>
<ENDPOINTS>
<WA>
[other optional objects...]
Note: if WA object is present in the request, the WA object MUST be
encoded after the ENDPOINTS object.
The format of the Wavelength Assignment (WA) object body is as
follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags |E|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Optional TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: WA Object Body Format
Flags (32 bits)
The following new flags SHOULD be set
o E (Explicit - 1 bit): When E bit is set to 1, this indicates that
the label assigned by the PCE must be explicit. That is, the
selected way to convey the allocated wavelength is by means of
Explicit Label Control (ELC) [RFC4003] for each hop of a computed
LSP. Otherwise, the label assigned by the PCE needs not be
explicit (i.e., in the form of label sets). This is to allow the
distributed WA.
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2.1.1. Wavelength Range Constraint
For any request that contains a wavelength assignment, the requester
(PCC) MUST be able to specify a restriction on the wavelengths to be
used. This restriction is to be interpreted by the PCE as a
constraint on the tuning ability of the origination laser
transmitter or on any other maintenance related constraints. Note
that if the LSP LSC spans different segments, the PCE MUST have
mechanisms to know the tunability restrictions of the involved
wavelength converters / regenerators, e.g. by means of the IGP. Even
if the PCE knows the tenability of the transmitter, the PCC MUST be
able to apply additional constraints to the request.
[Ed Note: to align with [PCEP-GMPLS]
WA TLVs:
*) WA_PREFERENCES_TLV (TBD) - Allow FF, LF, Random, vendor-specific
*) IPv4_ADDRESS_TLV | IPv6_ADDRESS_TLV | UNNUMBERED_IF_ID_TLV
*) LABEL_SET_TLV
The Wavelength is defined in [Lambda-Label] as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S | Identifier | n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
See [Lambda-Label] for a description of Grid, C.S, Identifier and n.
Note that each 32 bit Wavelength Field is designated to represent
one wavelength restriction on the associated link identifier.
2.1.2. Signal processing capability restrictions
Path computation for WSON include the check of signal processing
capabilities, those capability MAY be provided by the IGP, however
this is not a MUST. Moreover, a PCC should be able to indicate
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additional restrictions for those signal compatibility, either on
the endpoint or any given link.
The supported signal processing capabilities are the one described
in [RWA-Info]:
. Modulation Type List
. FEC Type List
. Bit rate
. Client signal
The Bit-rate restriction is already expressed in [PCEP-GMPLS] in the
GENERALIZED-BANDWIDTH object.
The client signal information can be expressed in the [PCEP-Layer]
REQ-ADAP-CAP object.
In order to support the Modulation and FEC information two new TLV
are introduced as endpoint-restriction in the END-POINTS type
Generalized endpoint:
. Modulation restriction TLV
. FEC restriction TLV.
The END-POINTS type generalized endpoint is extended as follow:
<endpoint-restrictions> ::= <VENDOR-ENDPOINT-RESTRICTION>|
<signal-compatibility-restriction> |
<LABEL-REQUEST><label-restriction>
[<endpoint-restrictions>]
Where
signal-compatibility-restriction ::=
<MODULATION-FORMAT>|<FEC>
The MODULATION-FORMAT and FEC TLV are described in the following
sections.
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2.1.2.1. MODULATION-FORMAT TLV
This optional TLV represents a modulation format restriction. This
TLV MAY appear more than once in the endpoint-restriction.
The TLV type is TBD, recommended value 17.
The TLV data is defined as follow:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|I| Modulation ID | Reserved |X|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Modulation ID/S bit dependent body |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The format follows the definition from [WSON-Encode] section 4.2.1
with the exception that the modulation length is already represented
in the TLV Length field.
The S and I bit are set as described in [WSON-Encode] section 4.2.1.
The Modulation ID is as defined in [WSON-Encode] section 4.2.1.
The X bit is set to 1 to exclude the Modulation format, the X bit is
set to 0 to include the modulation format.
The reserved bits MUST be set to 0 on transmit and MUST be ignore on
receive.
The rest of the TLV is encoded following [WSON-Encode] section
4.2.1.
2.1.2.2. FEC TLV
This optional TLV represents a FEC restriction. This TLV MAY appear
more than once in the endpoint-restriction.
The TLV type is TBD, recommended value 18.
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The TLV data is defined as follow:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|I| FEC ID | Reserved |X|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FEC ID/S bit dependent body |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The format follows the definition from [WSON-Encode] section 4.2.2
with the exception that the FEC length is already represented in the
TLV Length field.
The S and I bit are set as described in [WSON-Encode] section 4.2.2.
The FEC ID is as defined in [WSON-Encode] section 4.2.2.
The X bit is set to 1 to exclude the FEC; the X bit is set to 0 to
include the FEC.
The reserved bits MUST be set to 0 on transmit and MUST be ignore on
receive.
The rest of the TLV is encoded following [WSON-Encode] section
4.2.2.
2.1.3. New XRO sub-object: signal processing exclusion
The endpoint restriction only applies to the END-POINTS object.
The PCC/PCE should be able to exclude a signal processing along the
path in order to handle client restriction or multi-domain path
computation.
In order to support the exclusion a new XRO sub-object is defined:
the signal processing exclusion:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X| Type = X | Length | Reserved | Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-sub objects |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Attribute field indicates how the exclusion sub-object is to be
interpreted. The Attribute can only be 0 (Interface) or 1 (Node).
The sub-sub objects are encoded as in RSVP signaling definition
[WSON-Sign].
2.1.4. IRO sub-object: signal processing inclusion
Similar to the XRO sub-object the PCC/PCE should be able to include
a signal processing along the path in order to handle client
restriction or multi-domain path computation.
This is supported by adding the sub-object "processing" defined for
ERO in [WSON-Sign] to the PCEP IRO object.
2.2. Encoding of a RWA Path Reply
The ERO is used to encode the path of a TE LSP through the network.
The ERO is carried within a given path of a PCEP response, which is
in turn carried in a PCRep message to provide the computed TE LSP if
the path computation was successful. The preferred way to convey the
allocated wavelength is by means of Explicit Label Control (ELC)
[RFC4003].
In order to encode wavelength assignment, the Wavelength Assignment
(WA) Object needs to be employed to be able to specify wavelength
assignment. Since each segment of the computed optical path is
associated with wavelength assignment, the WA Object should be
aligned with the ERO object.
[Ed note: to align with [PCEP-GMPLS] the response WA MAY also
include
* SUGGESTED_LABEL_TLV
* UPSTREAM_LABEL_TLV
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* LABEL_SET_TLV
specifying the allocated labels according to the requested policies]
2.3. Error Indicator
To indicate errors associated with the RWA request, a new Error Type
(TDB) and subsequent error-values are defined as follows for
inclusion in the PCEP-ERROR Object:
A new Error-Type (TDB) and subsequent error-values are defined as
follows:
o Error-Type=TBD; Error-value=1: if a PCE receives a RWA request
and the PCE is not capable of processing the request due to
insufficient memory, the PCE MUST send a PCErr message with a
PCEP-ERROR Object (Error-Type=TDB) and an Error-value(Error-
value=1). The PCE stops processing the request. The
corresponding RWA request MUST be cancelled at the PCC.
o Error-Type=TBD; Error-value=2: if a PCE receives a RWA request
and the PCE is not capable of RWA computation, the PCE MUST send
a PCErr message with a PCEP-ERROR Object (Error-Type=15) and an
Error-value (Error-value=2). The PCE stops processing the request.
The corresponding RWA computation MUST be cancelled at the PCC.
2.4. NO-PATH Indicator
To communicate the reason(s) for not being able to find RWA for the
path request, the NO-PATH object can be used in the PCRep message.
The format of the NO-PATH object body is defined in [RFC5440]. The
object may contain a NO-PATH-VECTOR TLV to provide additional
information about why a path computation has failed.
Two new bit flags are defined to be carried in the Flags field in
the NO-PATH-VECTOR TLV carried in the NO-PATH Object.
o Bit TDB: When set, the PCE indicates no feasible route was found
that meets all the constraints associated with RWA.
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o Bit TDB: When set, the PCE indicates that no wavelength was
assigned to at least one hop of the route in the response.
o Bit TDB: When set, the PCE indicate that no path was found
satisfying the signal compatibility constraints.
3. Manageability Considerations
Manageability of WSON Routing and Wavelength Assignment (RWA) with
PCE must address the following considerations:
3.1. Control of Function and Policy
In addition to the parameters already listed in Section 8.1 of
[PCEP], a PCEP implementation SHOULD allow configuring the following
PCEP session parameters on a PCC:
o The ability to send a WSON RWA request.
In addition to the parameters already listed in Section 8.1 of
[PCEP], a PCEP implementation SHOULD allow configuring the following
PCEP session parameters on a PCE:
o The support for WSON RWA.
o A set of WSON RWA specific policies (authorized sender, request
rate limiter, etc).
These parameters may be configured as default parameters for any
PCEP session the PCEP speaker participates in, or may apply to a
specific session with a given PCEP peer or a specific group of
sessions with a specific group of PCEP peers.
3.2. Information and Data Models, e.g. MIB
module
Extensions to the PCEP MIB module defined in [PCEP-MIB] should be
defined, so as to cover the WSON RWA information introduced in this
document. A future revision of this document will list the
information that should be added to the MIB module.
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3.3. Liveness Detection and Monitoring
Mechanisms defined in this document do not imply any new liveness
detection and monitoring requirements in addition to those already
listed in section 8.3 of [RFC5440].
3.4. Verifying Correct Operation
Mechanisms defined in this document do not imply any new
verification requirements in addition to those already listed in
section 8.4 of [RFC5440]
3.5. Requirements on Other Protocols and
Functional Components
The PCE Discovery mechanisms ([RFC5089] and [RFC5088]) may be used
to advertise WSON RWA path computation capabilities to PCCs.
3.6. Impact on Network Operation
Mechanisms defined in this document do not imply any new network
operation requirements in addition to those already listed in
section 8.6 of [PCEP].
4. Security Considerations
This document has no requirement for a change to the security models
within PCEP [PCEP]. However the additional information distributed
in order to address the RWA problem represents a disclosure of
network capabilities that an operator may wish to keep private.
Consideration should be given to securing this information.
5. IANA Considerations
A future revision of this document will present requests to IANA for
codepoint allocation.
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6. Acknowledgments
The authors would like to thank Adrian Farrel for many helpful
comments that greatly improved the contents of this draft.
This document was prepared using 2-Word-v2.0.template.dot.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Resource ReserVation Protocol-
Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
January 2003.
[RFC3477] Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links
in Resource ReSerVation Protocol - Traffic Engineering
(RSVP-TE)", RFC 3477, January 2003.
[RFC4003] Berger, L., "GMPLS Signaling Procedure for Egress Control",
RFC 4003, February 2005.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4655, August 2006.
[RFC4657] Ash, J. and J. Le Roux, "Path Computation Element (PCE)
Communication Protocol Generic Requirements", RFC 4657,
September 2006.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) communication Protocol", RFC 5440, March
2009.
7.2. Informative References
[PCEP-GMPLS] Margaria, et al., "PCEP extensions for GMPLS", draft-
ietf-pce-gmpls-pcep-extensions, work in progress.
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[PCEP-Layer] Oki, Takeda, Le Roux, and Farrel, "Extensions to the
Path Computation Element communication Protocol (PCEP) for
Inter-Layer MPLS and GMPLS Traffic Engineering", draft-
ietf-pce-inter-layer-ext, work in progress.
[WSON-Frame] Lee, Y. and Bernstein, G. (Editors), and W. Imajuku,
"Framework for GMPLS and PCE Control of Wavelength
Switched Optical Networks", draft-ietf-ccamp-rwa-wson-
framework, work in progress.
[PCE-RWA] Lee, Y., et. al., "PCEP Requirements for WSON Routing and
Wavelength Assignment", draft-ietf-pce-wson-routing-
wavelength, work in progress.
[Lambda-Label] Tomohiro, O. and D. Li, "Generalized Labels for
Lambda-Switching Capable Label Switching Routers", draft-
ietf-ccamp-gmpls-g-694-lambda-labels, work in progress.
[WSON-Sign] Bernstein et al," Signaling Extensions for Wavelength
Switched Optical Networks", draft-ietf-ccamp-wson-
signaling, work in progress.
[WSON-OSPF] Lee and Bernstein," OSPF Enhancement for Signal and
Network Element Compatibility for Wavelength Switched
Optical Networks", draft-ietf-ccamp-wson-signal-
compatibility-ospf, work in progress.
[RWA-Info] Bernstein and Lee, "Routing and Wavelength Assignment
Information Model for Wavelength Switched Optical
Networks",draft-ietf-ccamp-rwa-info, work in progress.
[RWA-Encode] Bernstein and Lee, "Routing and Wavelength Assignment
Information Encoding for Wavelength Switched Optical
Networks", draft-ietf-ccamp-rwa-wson-encode, work in
progress.
[WSON-Imp] Y. Lee, G. Bernstein, D. Li, G. Martinelli, "A Framework
for the Control of Wavelength Switched Optical Networks
(WSON) with Impairments", draft-ietf-ccamp-wson-
impairments, work in progress.
[RSVP-Imp] agraz, "RSVP-TE Extensions in Support of Impairment Aware
Routing and Wavelength Assignment in Wavelength Switched
Optical Networks WSONs)", draft-agraz-ccamp-wson-
impairment-rsvp, work in progress.
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[OSPF-Imp] Bellagamba, et al., "OSPF Extensions for Wavelength
Switched Optical Networks (WSON) with Impairments", draft-
eb-ccamp-ospf-wson-impairments, work in progress.
8. Contributors
Authors' Addresses
Young Lee
Huawei Technologies
1700 Alma Drive, Suite 100
Plano, TX 75075, USA
Phone: (972) 509-5599 (x2240)
Email: leeyoung@huawei.com
Ramon Casellas
CTTC PMT Ed B4 Av. Carl Friedrich Gauss 7
08860 Castelldefels (Barcelona)
Spain
Phone: (34) 936452916
Email: ramon.casellas@cttc.es
Cyril Margaria
Nokia Siemens Networks
St Martin Strasse 76
Munich, 81541
Germany
Phone: +49 89 5159 16934
Email: cyril.margaria@nsn.com
Oscar Gonzalez de Dios
Telefonica Investigacion y Desarrollo
C/ Emilio Vargas 6
Madrid, 28043
Spain
Phone: +34 91 3374013
Email: ogondio@tid.es
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Internet-Draft PCEP Extension for WSON RWA March 2011
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